从活性骨钙素的代谢通路探讨"从肾论治糖尿病"的新机制

Treating different diseases with the same method is the unique treatment philosophy of Traditional Chinese medicine(TCM) and has been proved to be effective. But its scientific connotation still needs to be studied. Recent years researches have showed that osteoblasts can secrete active osteocalcin, which could improve the glucose metabolism. According to this theory, combining with the TCM theories and researches of treating diabetes from kidney and treating bone diseases from kidney, we think that active osteocalcin may be the internal link between these two treatments. On these grounds, we put forward the hypothesis: through its acting on osteoblasts, kidney-nourishing drug can promote the generation of active osteocalcin, thereby improving glucose metabolism. We use liuweidihuang pills as the kidney-nourishing drug and begin the research from two aspects, in vivo experiment in mice and in vitro cell culture. In vivo experiment we use insulin resistance mice model induced by high-fat diet through which we observe the effect of kidney-nourishing drug on blood glucose, insulin sensitivity ,insulin resistance and blood lipid etc. At the same time, the key indicators in the metabolic pathway of active osteocalcin are detected. Through these tests, we explore the relationship between the mechanism of improving glucose metabolism from kidney-nourishing drug and active osteocalcin. In vitro cell culture, we use the serum which containing kidney-nourishing drug or blank to incubate rat osteoblasts and / or pancreatic islets. Through the analysis between groups, we further verify the hypothesis and explore the mechanism of the kidney-nourishing drug about its improving of glucose metabolism. The significance of this research is that if we could verify the hypothesis, we will further improve the scientific connotation of treating diabetes from kidney, preliminary clarify its internal link with treating bone diseases from kidney and we could find more drugs from kidney-nourishing drug which can reduce blood glucose.

异病同治是中医学独特的治疗理念和行之有效的治疗方法，但其科学内涵有待研究。近年研究显示成骨细胞可以分泌活性骨钙素来改善机体的糖代谢，结合从肾论治糖尿病、从肾治骨的中医理论及研究，我们认为两者异病同治的内在联系可能是活性骨钙素，据此提出补肾中药能通过作用于成骨细胞促进活性骨钙素的产生，进而改善糖代谢的假说。课题采用六味地黄丸作为补肾方，从体内实验和体外细胞培养两方面着手。体内实验采用高脂饮食诱导的胰岛素抵抗小鼠模型，观察服用补肾方对血糖、胰岛素、血脂等指标及活性骨钙素代谢通路中关键指标的影响，探讨其改善糖代谢的机制与活性骨钙素的关系。体外细胞培养研究含补肾方的药物血清与空白血清作用于大鼠成骨细胞和/或胰岛β细胞，通过组间分析，进一步验证假说并探讨其机制。本研究的意义在于如证实该假说，将进一步完善从肾论治糖尿病的科学内涵，初步阐明其与从肾治骨的内在联系，并将为从补肾中药中挖掘新的降糖药提供思路

近年研究显示成骨细胞可以分泌活性骨钙素来改善机体的糖代谢，结合从肾论治糖尿病、从肾治骨的中医理论及研究，我们认为两者异病同治的内在联系可能是活性骨钙素，据此提出补肾中药能通过作用于成骨细胞促进活性骨钙素的产生，进而改善糖代谢的假说。课题采用六味地黄丸作为补肾方，从体内实验和体外细胞培养两方面着手。体内实验采用高脂饮食诱导的胰岛素抵抗小鼠模型，观察服用补肾方对血糖、胰岛素、血脂等指标及活性骨钙素代谢通路中关键指标的影响，探讨其改善糖代谢的机制与活性骨钙素的关系。体外细胞培养研究含补肾方的药物血清能否促进成骨细胞株产生活性骨钙素，并探讨其促进骨钙素产生的机制。.本研究发现1、六味地黄丸各剂量组均能明显升高未羧化骨钙素，能够改善HOMA-IR，改善胰岛素抵抗小鼠的糖耐量，其中尤以小剂量组更为明显；同时在体外细胞培养中进一步证实六味地黄丸药物血清能促进MC3T3-E1细胞株产生更多的未羧化骨钙素。2、体内与体外细胞培养中均发现六味地黄丸可以促进成骨细胞Runx2 mRNA和蛋白表达，而Runx2可促进骨钙素表达，这可能是其在骨钙素代谢通路中的关键作用靶点。3、在体内试验中，六味地黄丸能提高血清中骨钙素的浓度，能促进Runx2、ATF4、骨钙素mRNA和蛋白表达；在细胞培养中，六味地黄丸药物血清能促进MC3T3-E1细胞株增殖、促进Runx2及骨钙素mRNA和蛋白表达。这提示六味地黄丸对骨代谢具有正向调控作用。4、本研究在既往六味地黄丸降糖机制的基础上进一步阐明，六味地黄丸可通过升高未羧化骨钙素，改善胰岛素抵抗，改善糖耐量。这一发现丰富了从肾论治糖尿病的理论内涵，并初步阐明“从肾论治糖尿病”与“从肾治骨”的内在联系。.本研究的意义在于进一步完善从肾论治糖尿病的科学内涵，初步阐明其与从肾治骨的内在联系，并将为从补肾中药中挖掘新的降糖药提供思路。